Pipe-bending machine



II. P. CURTISI EIPEBENDING MACHINE'.

APPLICATION FILED AuGLI'L |920.

Patented D60. 27 1921.

2 SHEETS-SHEET I..

Patented D60. 27, 1921.

y -H;\rf..cun|s.f 'PIPE B ENDING MACHINE. APPLICATION FILED AUGJT. 1920.

UNITED STATES PATENT OFFISZE.

HOHER P. CURTIS, OF DENVER, COLORADO, ASSIGNOR OF ONE-HALF TO THE PLAINSIRON WORKS COHPANY, OF DENVER, COLORADO, A CORPORATION OF COLORADO.

PINE-BENDING MACHINE.

i-Sipeciaeabtcn of Letters Patent.

Patented Dec. 27, 1921.

Application led August 17, 1920. Serial No. 404,152.

To all w/wmt may concern:

Be it known that I Iiioiunii P. Gnarls, a citizen oi the United Statesof America, residing at the city and county of Denver and State of Col'"rado, have invented a new and useful Pipe-@enclin Machine, of which thefollowin isa speci cation.

My invention relates to a new and improved pipe bending machine, and theob'ects o my intention are:

First: to prov-ide a pipe bending machine that is adapted to receivelengths ot pipe and bend them into any desireff part of full circularcoils. l

Second: to provide a Inachinewhich is peeially adapted to bend largeiron or steel or copper pipes in `either portion or parts ot full coilsor into full coils, either at the ends of lengths of pipes o1' at anypart of their lengths. And

'Ihn-d: to provide a powerful and easily manipulated pipe bendingmachine on which pipe can be quickly placed and bent and removedtherefrom by any one or two mechanics.

I attain these objects by the mechanism illustrated in the accompanyingdrawings, in which:

Figure 1 is a side elevation of the 1mproved pipe bendingmachine, asection of pipe being supported thereby in position for bending.

Fig. 2 is a plan view thereof.

Fig. 3 is a transverse, vertical, sectional view of the same on the line3-3 of Fig. 2.

Fic.' 4 is a fragmental sectional view showing the manner of securingthe end of a pipe to the revoluble former, and also the mandrel, whichis supported in the pipe to prevent buckling or crumpling ot' the pipeat the bending point and for a distance back of that point.

Fig. 5 is a fragmental plan view, illustrating the manner of clamping along section of ipe when the same is to be bent inter nie iate of itsends.

Fig. 6 is an end View of Fig. 5.

Fig. 7 is a side view illustrating a modification in the pipe endclampin means.

Figs. 8 and 9 illustrate hat round U- sha ed pipe bends, res ectively.

4ig. l0 is a sectiona view of the former and its driven pipe abutmentroller, showing the circumferential gear tooth meshing pitch line of thesemi-circular gear of the former extending beyond the center oi'f thecurved pipe gripping groovezi of the former and its drum roller, inorder to make the driven roller move a trifle faster at its peripheralpipe engaging point than the turning speed of the pipe engaging grooveof the former.

Fig. l1 illustrates a perspective view ol? the plug Vthat clamps thepipe to the pipe bending former. And

Fig. 12 illustrates one manner oi" connectin the ends of pipe sectionstogether.

imilar reference numerals refer to sim-- ilar parts throughout theseveral views.

Referring to the drawings:

The numeral l, designates the bed plate or table of iny iinproifed pipebeni'ling machine, 'which is provided with supporting legs 2, and withbrackets 8, which are secured at their outer ends to the underside otthe 'trout portion of the bed plate and depend therefrom, and theirinner ends are integrally connected to form a journal boit e', in whichthe lower end oi a vertical shalt 5, is rotatably journaled` Gn theupper end of the shaft 5, is rigidly secured a gear wheel., preferably aworm gear 8, which is securely bolted to a revoluble circular table (i,which fits loosely in a circular opening iii the table 1, its uppersurface being flush with the upper surface of the table.

Upon the circular table is securely bolted a semi-circular casting 7,which constitutes a pipe bending former, as will presently be shown.

The worm gear 8, meshes with a worin pinion 8^, on a sliaii't 9, whififhmounted in bearings QA, secured to the underside oit' the table. Thes-,hail't 9, is also provided with a belt receiving conc pulley 1U, bywhich rotating power is connected to it and its shatt and to the wormpinion, and the worin gear, and consequently the vertical. shaft 5, andto the circular table 6, to which several speeds can be given by thedifferent step pulley portions on its cone 10. i

The bed plate is )i'ovided with two extension portions 11 anc l2. Theextension portion 11, is provided with two pairs ot T- shaped slots 13and 14, which arc positioned at a few feet apart, and to each of thesetwo pairs of T slots, blocks 15 and 1 6, are slidably mounted, and theyare secured adjustably in set positions to these slots by the bolts 17.These brackets support guide rollers 18 and 1.9on shafts 18A, and 19A,that llo are secinedvertically in the opposite ends 19B, of these blocksthat are formed on the opposite sides of a recess 19C, that is formed inthe inner ends of the brackets. rlhese rollers 1.8 and 19, are arrangedto act as guides and abutments to the pipes when bending them, as willbe fully described hereinafter.

The bed plate extension 12, extends far enough away from the guideroller 18, to receive on it, between the guide roller 18 and its outerend plate 20, the longest lengths of pipes or or' tubes or of casings21.

And my invention contemplates a pipe bending machine that is adapted tobend pipes made of either wrought iron, steel, copper, or et any othermalleable metal, from the smallest` sizes up to the largest sizes thatit is practical to bend and to use in tanks or for any constructionwork, requiring either straight or spirally coiled pipes.

rlhe extension 12, of the bed plate or table is also provided with legs2, and adjacent its-outer end, it is provided with parallel T slots 12A,in which are slidably mounted the headed ends of bolts 22, upon which issecured a bracket 20, by clamping nuts, as shown. The upright portion otthe bracket 20, is provided with a hole 'through which the threaded endor a rod 28, passes, and receives a nut 23A.

The opposite end of this rod 23, extends to and is threaded into one endof a mandrel 211, which may he of any predetermined length, but which Ipreferably make about ten times the diameter of the pipe to be bent.This mandrel is made to '.it loosely but snugly into the pipe beingbent. The opposite end 25, of the mandrel, for a short distance of aboutone-half or". the diameter of the pipe is tapered smaller in diameterthan the full diameter ci' the body portion of the mandrel, and itsextreme terminal end is rounded enough to allow it to be f4easilyinserted inte and pushed through th'e pipe that is placed on theextension portion oi vthe bed plate to be bent until its tapering endportion projects a short distance beyond the inner end of the pipe, aswill be fully described hereafter.

The former 7, is preferably oi" semi-circular shape, and as it issecured to the top of the t-able, it is rotatively turned by and withthe shaft and table. The outer peripheral edge of the pipe former ismachine iinished concentric to the vertical axis of the shaft 5, and theface of its peripheral edge is divided into a bottom stepped top rimportion 27, also into a central semi-circular concaved groove recessportion 28, and also into a gear tooth portion 29. The bottom rimportion 27, rests on the top surface of the table, and its steppedshouldered portion 30, fits over a projecting lip 31, that is -formed onthe bottom portion ot the guide roller 18, which is provided with astepped portion 32, ot the same size as the former, so that the lowerportions oli the pipe curving former and of the guide roller intersectand intermeshingly contact with each other as they rotate with a pipebetween them. The two opposing pipes receiving and tting semi-circulargrooves itting tightly around the circumference of the pipe, being bentas will be fully explained hereinafter.

The gear teeth of the upper portion ot the rim of the pipe former 7.meshes with a circumferential row of similar teeth that are formed onthe upper edge oi the face oit the guide roller 18, which thus becomes adriven roller, andthe face or this driven guide roller is provided' witha semi-circular recess curve 33, that is positioned directly opposite tothe pipe curve in the face et the pipe former 7, and these recess curvesin the faces ot the pipe former and in the driven roller 1S, must ritclosely around the circumference ol' theI pipe that is being bent;consequently, when pipes of different sizes are to be bent, pipe curvingformers 7 and driven rollers 18, oi different sizes made to lit tightlyaround the pipes must be provided and mounted on the table and in thebrackets l5 and 16; and it is tor this purpose that the driven roller18, is slidably mounted in its supporting extension portion ot the bedplates.

rlhe idler rollerA 19, also is provided with a recess groove 34, thatlits hall way around the size oi pipes that are being bent. This rolleracts as a rolling abutment to the side pressure of the pipes, which havea teudencv to swing away from the direction in which the pipes are beingbent, and consequently this idler roller 19, is adjustably placed andslidably mounted so that it can be moved to bear against pipesl ol :illsizes so that ils/can receive this side pressure.

,ln assembling the pipe curving former 7 and the driven roller 18, intopipe bending rel. ion with each other on the bed pl :ite oit my pipebending machine, it is necessary that they be so positioned that a linedrawn through their axial vertical centers. be a diametrically radialline through the diametrical center and axis of' the table and also ofthe driven roller, and that the center or the extension 12, be atangential line B; also that the pipes will be drawn straight throughand between the axial center ol the two oppositely pipe receivinggrooves in the former and in the driven roller, und they will bearagainst the abutment roller 19. Then the pipe. will be pinched tightlybetween the former and this driven roller: consequently also through thecenter ot straight lengths of pipe laid on the longitudinal center oithe extension 12 and the bed plate; and it is also necessary.I whenstarting to bend a pipe, that the pipe be placed on the extension 12,and that the mandrel be inserted in its rear end and be pushed throughit until its forward rounded end comes to the radial and diametricalcenter line A, in which position the mandrel is set and iixed byadjustably turning the nut on the end of the rod 23, against the back ofthe end plate 2() of the extension 12. The mandrel linserted in the pipeat this point until its full diameter is even with the line A. Theimmediate end of the mandrel is rounded, and this rounded portion wouldnaturally be a little smaller in diameter than the full body of themandrel and would project slightly beyond the point where the fulldiameter of the mandrel should be placed directly on this diametricallyand radial line A, as this is the point where the pipes start to bendwhen t-he curving action of the segment shaped former moves to curve itin either a partial or a semi-circular or a full circular curve.

When about to bend a pipe, the forward swinging end 26, of the pipecurving former 7, starts` to bend the pipe, with the center of the firsttwo or three or four teeth, preferably three teeth, of its forwardlyswinging end 2G, in mesh with the teeth of the driven roller, and withits front edge portion through the center of the first three teeth onthe diametrical center line A through the pipe former 7, and the axis ofthe driven roller 18, and of the rotating table.

After the former has been placed in the position described, the pipe isthen pushed a little beyond the end of the mandrel in order that it maybe secured to the forwardly swinging end of the pipe curving former,which is necessary as the end of the pipe, or at least that portion ofthe pipe where the curving bend is to start, has to be secured tightlyand rigidly to the forwardly swinging and moving end of the former.

My invention contemplates any means of securing the end of the pipesthat are to be bent, to the pipe former 7, which, as it swings aroundwith the rotating movement of the table, must carry the pipe clampedtightly at its end to it, and around with it in order to bend it. Ipreferably, however, carry out this feature of my invention in thefollowing manner:

0n the forwardly swinging movement end of the pipe curving formen, Icast a lug 26, and in the end of the pipe 21, that is to be bent, Iinsert a short plug 27B, which fits snugly therein and is provided withsharp edged circular bands 27A, that are beveled to permit their sharpedges to cut into the inner surface of the pipe and grip it, as will bepresently explained. This plug 27B, is provided with a head portion 28D,extending in a radial direction toward the former; the plug 27B, is alsoprovided with a lug 28A, that projects at right angles from the headpiece 28D, and extends alongside of the pipe 21, and overlaps looselythe lug 2G, on the forn'ler, and a set screw 28, is threaded through thelug of the plug to bear against the lu-g 26, of the former, and thusclamp the plutIr and the end of the pipe 21, to the former. This plug,with its head and lug portions, forms a U-shaped coupling for connectingthe end of the pipe that is to be bent, to the former, and when theformer starts to turning, it pushes against the set screw, andconsequently the plug and the sharp edges of the bands on the plug aredrawn tightly against the inner surface of the pipe by the set screw28B. Consequently when the former starts to turning, its lug pushesagainst the set screw and the plug and the sharp edged bands on the plugdig into it and tightly grip it and force it to move with the formerwithout slipping movement between them. IVhen, however, a semi-circularcurve is to be formed in the center or in a part of the length of apipe, as indicated in Fig. 5, a yoke-shaped clamp 29A, is employed,which is placed over the pipe, as shown, its ends, which are threaded,extending through holes in the lug These threaded ends of the clampreceive clamp nuts 30A, which, when tightly screwed against the lug 26,cause the clamp 29A,` to rigidly secure the pipe to the former 7 A block28C, may be inserted in the pipe to the point where the clamp 29A,engages the pipe, to prevent the pipe from being indented by the clamp.

In making a half round bend, however, the pipe is positioned on themandrel and 105 between the semi-circular grooved recesses of the pipebending former and its opposingdriven roller 1S, so that the plug 27B,can be inserted in the pipe and the screw tight ened, then the plug andthe pipe are clamped 110 tightly together to the lug of the pipe bend*ing and curving former. It is only then necessary to move the idlerroller 19, against the pipe, and the machine and the pipe are ready tobe started and the pipe curved and 115 bent as desired. The operation ofbending or curving pipes into quarter circles or half or semi-circles orfull circles, being as follows: Y g

Having set the mandrel with the pipe on 120 it in the semi-circulargrooves between the former and its driven roller and securely clamped tothe former, the pipe is supported on its inside by the mandrel, and itis held tightly in the semi-circular grooves of the 125 former and itsdriven roller; consequently, it cannot be flattened or dented as it isdrawn around the former. Rotativo power is then applied to the conepulley, and the table is rotated slowly by the gears and cone' 130pulley end theii1 supporting' inemheis. Then it the 'eiinei eeciies thepipe ni'otnd e. euived tine e i 'd t t ceiitei for :i heh oi" e.iiei-rohition, zint. it the nieeh'ine is sto psd zitte? iiiniing halt oV'i i'evohitieii, s. seinieeiieiilsi bend is termed, is shown in Pigs. 8end 9, but if it is eei'iied initie-.ily

around to subs a uil i'evohitioii, ziy full eiieuiei eii oii'ned in thepipe.

The abutment i011 i een he moved to engag e the sides 0i p'oes thatplaced on 4he extension i2) and eeeiiet. i and its tod eff te one sideet t'li line i3. This is done bi.' ni

phiee, and is used Whei' s wanted in the pipe and en ends of the pipeeiie i'equ` eetain angle to e end is required te te the Curve itseif.

find in piii eiieuhii1 coils et z l 1i@ L( When they fiie ma. `iipe of'iibeiit iai'ein two inches up to six inches in diameter, thiit the pipebe nitide into semi-ei eiihii coiis and then that theiil en is heseeiiiee. together by any suitable ineens. l). pi'ei' use the angedclamping ineens in Fig. l2.

i ininhei1 et heit eiifeuhii eeiis een he seeiiied togethei in thisine-.nner7 and by raising them se as to puh thein iipiiit, zi 'tutieiieuiai spiral eoil is obtained freni the tiet seiiii-eiieuiei eoiisformed en machine.

find in practice that with thiol;

pipes it is an eeiientege to neve the itoiinei rotate its pipe abutmentioifei 18.. se that the pipe gripping groove of this di'iiei iioiiei 18,will tr Just a little :sistei than iiphefai siii'feee et the p' Jegrippin;I of the form-i1. which the pei'inheiiei A is in ioiliii he peoi i diiven roller. .-n tiis figure the sei of the i'oimei than itseoneentiieefi ranged pipe gripping gieove, and th eumferentiai i'ow o'geen roher is :made of any yi'edeteiimned eine teeth on the diven sizeiii diametei th ii t e pipe giiippinjg giooiie. Consequently, by thiseoopeieaiiie eianpeneiit the pipe gripping periphery et 'he diivenzoiiei moves tester then the pipe gripping' Groove of the toiiiiei, andthe increase .n the turn- .fi I an hiiiie ein inpie, pinenp; iiiiiehineinetei, :ind white I have tted the pieteiied construction and eii'i ipeinent oit it I. do not wish to he hniitet` to L. :is ehsiiies niiilvhe incide With- `i ifiein the spirit et my inven- 'i invention, schat .ete seeiiife hy Let- J v n l. eiiihinzitien with i pipe bendinginfiehine., et the hed phite end its shaft heziis, the i'eitieu hi'tjeiiiniiied therein .find

S ei hnrr shove seit ed piste* with :i eiriiiole inoiiiited oi endseeiiied to said shaft, ineens including gearing and e multiple sneed pthey 'for rotating seid tnhie5 :ind With the pipe curving foiineiieinoi'iihiy iiied to the top of sziid tiihle, siiid former 0o .ii.ising :i Casting having :i huh ineiiihei i' ioi'iihiy mounted en :indseeiiied to the sfiid 'veitiezii shiiiit. sind ii peiipheiiilpei'tioiir` the 'iee of which eontiiins ii, stepped shouidei et itshottoin edge, e seini-eiieuhii groove iii its veiitiiii portion:idiipted te fit iiouiid pipe. :ind gear-toothed poi-tion fit ts upeei'eti/fe portione find with the driven oUei' adjust if ineiinted iii pipeenofming `i l e 'ieiiiihei'iii portion of sind :ivi ii teeth iii'oiiiidits i` with the geni' teeth of pifoi'ided -with :i semi-viren l Y fingoove positioned opposite to pipe ieeeiifingij pgioove in sziid toi-nier,in having stepped bottoni edge poitioii ,tin into the stepped portion inthe bottoni seid oi'iiiei.

.pipe hendinp; machine, Jdie eoinhifoiniei provided with gi'eiii teeth,itih o ,if whiwh is ot hiigei izidiiis ien its pipe tiiilg eini'ej with:i ifoiiei' pi'ovided with pipe Fitting gijioove registering; oppositethe pi .e i'ittiiie gijioove ot seid ifoi'inei', sind provided with :ieii'eiiiiitei'entiiil ioi-.if ot geni' teeth oi siiiiiliei diiiineteithiin its pipe fitting giioove, and in niesh with the geni.' teeth otseid 'foi'nien In ii pipe bending iniiehine, the eoinhination With e.foi'inei comprising' :i seinieii'euhii pgeiii, :i geni' of hissdiziinetei in niesh TVith the"semieiieiiliiif geni', siiid gijeiiishiiving; portions piovided with iiniiuhii, copei`- the end of the pipeis clamped to the projection; means for rotating the former, and anadjustable abutment roller for preventing outward movement of the unbentportion of the pipe.

4. In a pipe bending machine, the combination of a former comprising asemi-circular gear having an extension on one end, a. gear oi lessdiameter than the semi-circular gear and in mesh therewith, said gearshaving portions provided with registering grooves adapted to receive apipe to be bent; a U-shaped clamp, one end of which is adapted to beinserted in the forward end of the pipe and is formed with annularknife-edged pipe gripping elements, the other end extending behind saidextension and is provided With a bolt which is adapted to be screwedagainst said extension, thereby to clamp the end or the pipe thereto, acircular table to which said former is bolted, means for rotating saidtable, and an adjustable abutment roller for preventing outward movementof the unbent portion of the pipe.

.5. In a pipe bending machine, `the combination with a former comprisinga semicircular gear, a gear of less diameter than the semi-circular gearand in mesh therewith, said gears having portions provided withregistering grooves adapted to receive a pipe to be bent, of alongitudinally adjustable mandrel adapted to be inserted in said pipe,the forward end of which extends to the bending point of the pipebetween the tivo gears, an extension on the end of the semi-circulargear next the forward end of the pipe, and means for securing theforward end of the pipe to said projection, a circular table to whichsaid semi-circular gear is screwed, means for rotating said table, andan abutment roller at a point coincident with the rear portion of themandrel, for preventing outward movement of the unbcnt portion of saidpipe.

G. In a pipe bending machine, a table, a circular plate in the surfaceof said table, and gearing t'or rotating the same, a half round formersecured to said plate, having gear teeth thereon, an adjustable bearingon said table, a gear .mounted in. said bearing and :in mesh with saidformer, said former and said gear having portions provided withregistering groei/es to receive a pipe to be bent, an extension on theend of the former next the gear, and means for clamping the end of apipe .inserted between said former and gear, to said extension, amandrel inserted in said pipe, a rod secured to the rear end oi saidmandrel, an adjustable block on said table to which the free end of saidrod is adjustably secured, the forward end of said mandrel being roundedand extending slightly beyond the bending point of the pipe, and anadjustable bearing on said table, and an abutment roller mounted in saidbearing and engz'iging said pipe at a point coincident; with the rearportion of the mandrel, to prevent outward movement of the pipe Whilebeing bent.

In testimony whereof I ailix my signature in presence of two witnesses.

l-IOMER P. CURTIS. Witnesses R. B. MCCONNEY, R. E. ArrLnQUrs'r.

